When Novell and Microsoft announced their unlikely partnership, a part of the arrangement that got little attention at the time was that they'd create a joint research facility, where both company's technical experts would collaborate on new joint software solutions. Now, they're staffing up.

What Linux really needs is open specifications for communicating with Exchange Server. I don't see Exchange interoperability listed in the agreement, and I'm really disappointed in Novell for not pushing for this.

I don't think there was any mention of this, mostly because it's already available. There is an Exchange connector available for Outlook/Exchange interoperability. It's GPL.

From the server end, it would be an almost inpossible task to get Exchange server modules working on Linux. They would have to port AD over if I'm not mistaken.

If you want a cross platform groupware system, use GroupWise. It works fine on mulitple platform on both the server and client(although the cross platforms GroupWise client leaves a bit to be desired).